Checker brick and checkerwork



sept 5, 1933. A. w. sMlTH ET AL CHECKER BRICK AND CHECKERWRK Filed July 23, 1931 WITNESS Patented Sept. `5. 1933 UNITED STATES PATENT .OFFICE CHECKER, BRICK AND CHECKERWORK Ohio Application July 23, 1931. Serial No. 552,634

l Claims.

The present invention relates to checker bricks and to checker work, such as that usually employed in hot blast stoves, open hearth furnace regenerative chambers and like heat exchanging structures, intended to receive and retain for brief periods the heat carried by currents of heated gaseous fluids, as, for example, furnace exhaust gases, and subsequently to impart such heat to relatively cold currents of similar fluids, such as air or fuel gases, the checker work being formed within a suitable chamber from a plurality of checker bricks.

Under such conditions it is the usual practice to rst pass heated exhaust gases through the chamber in one direction to heat the checker work to a relatively high temperature and to then pass the gas or air which is to be heated through the now hot checker work in substantially the opposite direction, the checker work usually being built up from refractory bricks of suitable form in such a way as to provide a plurality of vertical passages adapted to permit free flow of the gases through the chamber and to present relatively large aggregate surfaces for heat exchange by contact of the gaseous uids therewith. There have also sometimes been provided horizontal passages interconnecting adjacent vertical passages in the checker work with the objects of increasing the area of the heat exchanging surfaces and of producing turbulence in the flow of the gases in order to bring as large a portion thereof as possible into direct contact therewith and thus obtain a maximum heat transference therebetween.

It has been found that in checker work of this character an appreciable degree of turbulence is produced by the horizontal passages referred to and that the heat transference is somewhat greater than when such passages are not provided, but even with the best forms of checker bricks and checker work with which we are familiar maximum efficiency in the exchange of heat between the checker work and the gases passing therethrough is not obtained, thus resulting in operating losses which, although extremely undesirable in modern industrial practice, have heretofore been substantially unavoidable.

A principal object of our invention, therefore, is to provide a checker brick of improved form which, when built up with a plurality of other similar bricks to form checker work, is effective to insure maximum. heat transference between the checker work and the gaseous fluids which pass therethrough.

Another object of our invention is to provide such a brick which is effective to constrain the gaseous fluids, in their Apassage between the top and bottom of the checker chamber, to pursue an. irregular or tortuous course, whereby greatly increased turbulence of the stream and more effective contact of all portions thereof with the heat-exchanging surfaces of the checker work is brought about than in the checker work heretofore in general use.

A further object of our invention is to provide means whereby more effective heat exchange' in a checker chamber, or the like, of given size may be produced than has heretofore been feasible ancl whereby, as a corollary, a smaller chamber than has heretofore been required may be employed for effecting a given amount of heat exchange.

A still further object of our invention is the provision of improved checker work n which the gases are conducted through a plurality of `tortuous passageways, whereby thorough intermixture and uniformity in temperature of all portions of the gases and maximum heat exchange between the checker work and the gases are effected.

Other purposes, objects and advantages of our invention will hereafter more fully appear, or will be understood from the following description in which reference will be had to the accompanying drawing.

In the said drawing, Fig. l comprises top plan, side elevation and end views of a single brick constructed in accordance with our invention and of a form we prefer to employ. Fig. 2 is a fragmentary top plan view on smaller scale of a plurality of such bricks built up, as for example in a hot blast stove, to form our im.- proved checker work; Fig. 3 is a vertical section of the checker work shown in Fig. 2, on the line 3-3 in said figure and Fig. 4 is a somewhat similar sectional view but taken on a plane normal to that of Fig. 3, as along the line 4-4 in Fig. 2. In the several figures like characters are used to designate the same parts and the various sections are taken looking in the direction of the arrows on the indicated section lines.

Referring now more particularly to the drawing, that form of our checker brick, shown in Figs. 1 4, inclusive, which will usually be preferred, comprises a main body 1 of suitable refractory material which is substantially rectangular and has projecting from its front face 1a a pair of angular ribs 2, while spaced semicylindrical grooves 3 extend vertically of the back face 1b for a purpose hereafter to be described. The ribs 2 desirably extend from the plane of the top of the brick angularly downwardly across its front face approximately to the plane of its midpoint and thence angularly in reverse direction to the bottom face of the brick to end approximately in the same vertical plane as their respective points of origin, as clearly shown in Fig. l. The central portions of the ribs are desirably cut away, as at 5, to afford transverse passageways when the ribs are in abutting relationship with other bricks, while the lands 6 on the front faces of the ribs above and below the cutout portions 5, are provided with substantially semicylindrical vertically extending tongues 7 adapted to t into the ends of the grooves 3 in adjacent bricks to enhance the rigidity and relative immobility of the builtup structure.

When checkerwork is to be built up from bricks of this character, we prefer to lay the bricks in each course end to end in rows with the joints in adjacent rows staggered, as shown in Fig. 2, that is, the tongues 7 on each brick are fitted respectively into 4one of the grooves 3 in each of two bricks in the adjacent row, and by this interlocking of adjacent bricks and rows, a high degree of inherent stability and rigidity is attained. Additionally, the joints between the bricks of one course and those of the superjacent course may likewise desirably be staggered by turning the bricks in the latter so that their corresponding faces lie in planes substantially at right angles to those of the bricks in the former and withl the planes of the joints in the respective courses also laterally offset as clearly shown in Figs. 3 and 4, but with the passages 8 provided between the ribs 2 of the bricks in the respective courses in registry with each other.

As the gases pass through the ,checker work the paths of their travel are angularly changed in each course by the angularity of the passages 8 dened by the ribs, and likewise, when passing through the corresponding passages in the subjacent or superjacent course, these paths are again angularly changed but in a different vertical plane, thus effecting tortuous movement of the gases which effectively brings a maximum portion thereof into direct contact with the brick surfaces. Additionally, the horizontal grooves 5 form transverse passageways 9 connecting, in the built-up checker work, the tortuous passages 8 and serve to increase the turbulence of the streams of gases, thus still further enhancing the direct contact thereof with the brick surfaces and aiding in thoroughly intermixing all portions of the gas so that the latter issues from the checker chamber at a substantially uniform temperature throughout.

While we have herein illustrated and described with considerable particularity checker bricks of the form we prefer to employ and checker work constructed therefrom in accordance with our invention, we do not thereby desire or intend to restrict or conne ourselves thereto as the bricks are capable of modification in numerous particulars and may be assembled in the formation of checker work or the like in various ways other than that to which we have referred without departing from the spirit and scope of the invention as dened in the appended claims.

Having thus described our invention, we claim and desire to protect by Letters Patent of the United States:

1. A checker brick of the class described having parallel front and rear faces and parallel top and bottom faces, and a pair of spaced ribs projecting outwardly from the front face between said top and bottom faces and defining opposite sides of a passageway extending obliquely thereto, each rib having a transversely extending groove intermediate its ends disposed substantially parallel with said top and bottom faces and interconnected with said passageway.

2. A checker brick of the class described comprising a generally rectangular body having its opposite faces disposed in substantially parallel relation, a pair of spaced ribs extending from one of said faces and arranged to define between them a passage having portions extending in oblique relation with each other, the central parts of the ribs being cut away on opposite sides of the passage to form other passages extending laterally therefrom.

3. A checker brick of the class described comprising a generally rectangular body having its opposite faces arranged in substantial parallelism, one of said faces being provided with a pair of spaced grooves extending from the top to the bottom of the body, a pair of spaced ribs extending from that face of the body opposite to that provided with the grooves and each having portions arranged in angular relation to each other to thereby dene between the ribs a passage extending in different directions, each of said ribs having a tongue projecting from its outer face adapted to enter'one of the corresponding grooves on an adjacent brick when assembled therewith to assist in locking the several bricks together.

4. A checker brick of the class described comprising a generally rectangular body having its opposite faces arranged in substantial parallelism, one of said faces being provided with a pairl of spaced grooves extending from the top to the bottom of the body, a pair of spaced ribs extending from that face of the body opposite to that provided with the grooves and each having portions arranged in angular relation to each other to thereby dene between the ribs a passage extending in different directions, each of said ribs having a tongue projecting from its outer face adapted to enter one of the corresponding grooves on an adjacent brick when assembled therewith to assist in locking the several bricks together, and the central portion of each of said ribs being cut away to provide a transverse passage extending outwardly from the iirst mentioned passage.

5. In checker work of the class described, a plurality of superposed courses formed of individual bricks disposed in each course in abutting relation and providing therein a plurality of passages extending angularly therethrough in planes respectively substantially normal to the corresponding planes of the passages in registry therewith in next adjacent courses, the upper end of each passage in each course being in substantial vertical alignment with its lower end.

6. In a checker work of the class described, a plurality of superposed courses formed of individual bricks, each of said bricks having a pair of angular ribs projecting outwardly from one of its faces and abutting an opposite face of an adjacent brick in the same course to thereby define a tortuous passage between the top and bottom of said course, and the several passages in each course registering at their ends with corresponding passages in the adjacent courses.

7. In checker work of the class described, a plurality of superposed courses formed of individual bricks, each of said bricks having a pair of angularribs projecting outwardly from one of its faces and abutting an opposite face of an adpassages in each course registering at their ends with corresponding passages in the adjacent jacent brick in the same course to thereby define a tortuous passage between the top and bottom of the course, and an outwardly extending tongue carried by each of said ribs engaging the said adjacent brick in a vertically extending groove COllrSeS formed in said opposite face thereof, the several 

